Prior means for securing telescopic sights to handguns have included use of non-integral spaced-apart sight bases secured to the frame and the barrel. Such barrel and frame-mounted sight bases have necessarily included drilled and tapped screw holes in the barrel and frame for receiving mounting screws which in some instances could compromise desirable frame and barrel strength levels. Furthermore, the prior arrangements, which included a separate sight mount base attached to the firearm by screws and to which telescopic sight mounts were affixed have not proved entirely satisfactory since the separate base and its relatively small attaching screws are subject to loosening by recoil, vibration, and handling.
U.S. Pat. No. 4,531,321 discloses a clamp-type arrangement that fits over a revolver frame which arrangement is subject to loosening under recoil and the frame of the revolver depicted therein is not specifically machined to accept rigid scope mounts.
The arrangement depicted in U.S. Pat. No. 3,611,606, owned by the assignee of the present application, has been utilized by such assignee on revolver barrels but the results have not been entirely satisfactory due to the distance of the telescopic sight from the eye and the mass of the telescope and mounts located on the barrel. Furthermore, machining a rounded barrel to accept this prior patented system is difficult and costly. U.S. Pat. No. 3,611,606 discloses an arrangement for mounting a telescopic sight on a rifle receiver in which forward and rearward sight mounts engage accurate recesses integrally formed in the rifle receiver.
No prior revolver has yet incorporated an entirely suitable means for mounting barrel and a telescopic sight directly onto its frame without compromising strength and avoiding the problems associated with mounting such a sight with separate bases affixed to the frame via screws, or to mounts on the barrel.